How do I have create two Front Ortho Viewports with different reference images on each?
You can use &quot;Local Collections&quot; filters in each viewport to filter out your different backrounds.
Place each of your images in a different collection.
Place your work objects in a third collection.

Create 2 viewports by click-dragging the edge of the 3D viewport.
Expand the &quot;N&quot; panel, then go to the &quot;View&quot; panel, go down to &quot;Collections&quot; and check &quot;Local collections&quot; in both viewports.
Now click the eye icon of the background collections in each viewport.
Result :